Liquid marker and replaceable ink cartridge therefor



Sept. 23, 1969 P. w. STRICKLER LIQUID MARKER AND REPLACEABLE INKCARTRIDGE THEREFOR Filed Dec. 21, 1966 o {O \A 2 m A p 1 o 2 4 2 3ITIYENTOR. FKEDERKLK W S RlCKLER ATTCIRNEY United States Patent US. or.401-199 1 Claim ABSTRACT OF THE DISCLOSURE A liquid marker having incombination a permanent outer casing assembly and a replaceable innerink cartridge assembly. The outer assembly consists of a tubular barrelhaving a closed end, a screw-threaded sleeve fixed within its closedend, and a closure cap having a closed end and a cap insert in itsclosed end. The replaceable ink cartridge assembly has as its principalelement an elongated tubular barrel open at both ends and having aninternal taper at decreasing diameter toward its externally taperedforward end. A writing nib adapter is fixed in the forward end of thebarrel. The cartridge barrel is substantially filled by an ink absorbentreservoir whose forward movement within the cartridge is limited by aninternal abutment. A writing nib extends through the nib adapter intocontact with the reservoir. The rear end of the cartridge through whichthe absorbent reservoir is inserted is sealed by a threaded end plugwhich engages the threads of the barrel insert in the closed end of theouter barrel to old the barrel assembly and the cartridge assemblyreleasably engaged with each other.

SUMMARY OF THE INVENTION The primary structure comprising the inventionresides in the threaded barrel insert in the end of the permanent outerbarrel in combination with the threaded end plug of the replaceable inkcartridge by which the outer barrel and the ink cartridge are releasablyheld together to form the marker. Contributing structures reside in theinner taper of the ink cartridge and the absorbent reservoir stops atits forward end.

It has been conventional, for many years, to provide replacement inkcartridges for fountain pens using liquid ink as the writing fluid. Inall cases, these prior pens have had permanent writing nibs at one endand were refilled by inserting a vial of liquid ink behind the nib byentry into the pen barrel at some point behind the nib. These priorstructures and practices do not lend themselves for application toliquid marking devices, wherein a marking liquid is wholly absorbed inan absorbent reservoir within the pen barrel and is fed by capillaryaction through a porous writing nib. In these latter implements, this isnot feasible because the nib, the absorbent reservoir, and its inkcontent must be supplied as a self-contained unit. A unit, as described,cannot be assembled with an outer casing in the manner of the earlierrefillable fountain pens. The novel structures of this application adaptliquid markers to renewal and refilling practices.

Liquid marker refill cartridges are presently available on the marketbut all of them to date have been in the form of very slender cylindershaving only a limited ink capacity. The screw-threaded cartridge closureplug extension of reduced diameter herein requires no reduction in thediameter of the cartridge and, therefore, preserves the full inkcapacity of the cartridge while also providing positive means forconnecting the cartridge and the barrel of the marker.

It is the purpose of the invention to provide a liquid marker which hasa permanent outer barrel open at one end and a threaded insert in theopopsite end thereof, and a replaceable ink cartridge within the barrelwhich has therein an absorbent ink reservoir and, extending from one endof the cartridge, a writing nib having its inner end in contact with theabsorbent ink reservoir, and in which the opopsi'te end of the cartridgeis closed by a screw-threaded plug, whereby the threads of the plug areadapted to engage the threads of the insert and thereby hold theassemblies together as a writing unit.

BRIEF DESCRIPTION OF THE DRAWING The foregoing structures, the purposeof the invention, and its advantages will be more fully understood byreference to the drawing, which illustrates a presently preferredembodiment, when viewed in light of the detailed description to follow.In the drawing, like reference numerals indicate like parts, and;

FIG. 1 is a cross-sectional view along the axis of the marker;

FIG. 2 is a foreshortened external view of the marker with its closurecap removed;

FIG. 3 is an external view of the replaceable ink cartridge;

FIG. 4 is a cross-sectional view along the axis of the permanent outerbarrel assembly;

FIG. 5 is a transverse sectional view on line 5-5 of FIG. 1; and

FIG. 6 is a transverse cross-sectional view on line 6-6 of FIG. 1.

DETAILED DESCRIPTION The marker herein consists essentially of apermanent outer barrel assembly 10, more particularly shown in FIG. 4,as consisting of an outer barrel 12, a cap 14, a barrel insert 16 and acap insert 18. The barrel 12 and the cap 14 are preferably formed ofmetal and may be suitably ornamented, if desired. Both the barrel 12 andthe cap 14 are in the form of a tubular shell closed at one end. Theclosed ends of these shells are preferably somewhat tapered and the openends are so related in diameter as to permit the cap to telescope overthe open end of the barrel with a sufficiently snug fit to keep the twoshells assembled when the cap is so telescoped over the open end of thebarrel. The tapered closed end of the barrel 12 receives the internallythreaded barrel insert 16 with a press fit so that the barrel insert 16is held firmly within the closed end of the barrel.

The cap insert 18 within the closed end of the cap shell has formedthereon an annular shoulder 20 which fits snugly against the inner wallsurface of the cap 14 and holds it in place within the cap.

The permanent barrel assembly 10 receives therein a replaceable inkcartridge assembly 22. This assembly is preferably composed of moldedplastic material such as polypropylene. The replaceable ink cartridgeincludes a cartridge barrel 24 which is in the form of an elongatedcylinder adapted to fit snugly into the outer barrel 12 and the cap 14.The cartridge barrel 24 has one end closed by an end plug 26 while theexternally tapered opposite end of the barrel is adapted to receive anib adapter 28. In its preferred form, the cartridge barrel 24 isinternally tapered from a larger diameter at the end closed by the endplug 26 to a smaller diameter at its opposite end thereby providing aslight annular space 30 between the outer surface of an absorbentreservoir 32 and the inner wall of the cartridge barrel.

The absorbent reservoir 32 is composed of a pourous felt-like materialwhich is highly absorbent of liquid ink or other marking liquid. Theabsorbent reservoir 32 is inserted into the cartridge barrel 24 throughthe open rear end thereof prior to the insertion of the end plug 26. Theend plug has an annular shoulder 34 adapted to abut the open end of thecartridge barrel 24. A sleeve 36 extends inwardly of the shoulder 34into tight contact with the inner wall face of the cartridge barrel.After the absorbent reservoir 32 has been inserted into the cartridgebarrel, and has been saturated with ink or other writing fluid, the endplug 26 is applied to the open end of the cartridge barrel and sealedthereagainst, if necessary. Such sealing can be done in any suitable waysuch as by the use of an adhesive or by spin welding, for example.

The end plug 26 is externally screw-threaded to engage internal screwsof the barrel insert 16. Thus, in assembling the replaceable inkcartridge 24 with the permanent outer barrel assembly 10, the inkcartridge is inserted into the outer barrel 12 until the screw threadsof the barrel insert 16 and those of the end plug 26 come intoengagement with each other. The replaceable ink cartridge assembly andthe permanent outer barrel assembly are then relatively rotated in adirection to more fully engage the threads of the end plug and thebarrel insert until the open end of the outer barrel 12 abuts an annularshoulder 38 on the cartridge barrel.

The external surface at the forward end of the cartridge barrel 24 isinwardly tapered to correspond to the taper of the cap insert 18, sothat an ink-tight seal is produced, and to provide a comfortable fit inthe finger of the user. The nib adapter 28 has extending therefrom oneend of an axial writing nib 40, the inner end of which is embedded in,or at least lies in substantial contact with, the end of the absorbentreservoir 32. The outer end of the writing nib 40 extends beyond the nibadapter 28 where it is exposed for contact with the paper or othermaterial which is to be marked. The writing nib 40 is a slender, porousbody which is preferably quite rigid and resistant to the abrasionencountered while using the liquid marker. Such materials as sinteredplastic or metal, or linear fiber, have been suggested.

The nib adapter 28 is simply a sleeve-like element which firmly holdsthe writing nib 40 within its axial bore and has a body portion which ispress-fitted into the end of the cartridge barrel in order to make theassembly liquid tight.

Contact with the absorbent reservoir 32 prevents the nib 40 from movinginwardly under writing pressure. The absorbent reservoir 32 is heldagainst longitudinal movement within the replaceable ink cartridgeassembly by means of a plurality of internal ribs 42 which limit themovement of the absorbent reservoir 32 in the forward direction and bythe end plug 26 which limits the longitudinal movement of the absorbentreservoir 32 in the opposite direction.

When the replaceable ink cartridge assembly 22 is handled, shipped andstocked, as a marker refill unit, its nib end will be suitably enclosedas, for example, in a cap similar to the cap 18 to avoid evaporation ofthe marking fluid. Such cap or enclosure is removed and discarded whenthe replaceable ink cartridge assembly is placed into the permanentbarrel assembly for use therein.

The fit between the outer barrel 12 and the cartridge barrel 24 may beenhanced by providing the cartridge barrel with a plurality of externalribs 44, as seen in FIG. 6. Such external ribs improve the contactbetween the outer barrel 12 and the cartridge barrel 24 and insure thatinadvertent separation of the two is avoided.

From the foregoing, it can be seen that a very simple, yet reliablereplaceable ink cartridge assembly has been provided for markingimplements of the type described. When the marking fluid of the deviceis exhausted, to remove the cap 14, it is merely necessary to turn thecartridge barrel 24 in respect to the outer barrel 12 until the screwthreads of the end plug 26 are disengaged from the barrel insert 16. Thereplaceable ink cartridge assembly may then be withdrawn from the outerbarrel 12 and a replacement can be substituted by reversing the process.The use of a replaceable ink cartridge assembly, long common inconventional liquid ink fountain pens, makes possible, in a liquidmarker type of instrument, the construction and design of a permanentouter barrel assembly which does not seriously sulfer from costlimitations since the permanent barrel assembly 10 can now be reusedindefinitely and can, therefore, be designed to meet the most fastidioustastes. The replaceable ink cartridge assembly can be very inexpensivelymanufactured so that no substantial loss is felt when it is discardedupon displacement.

The liquid marker has been specifically illustrated and described in asingle embodiment for the purpose of disclosing a presently preferredform of the invention. It is evident that the invention is useful notonly in pocket type markers, but equally in other types, as, forexample, in desk-set markers and the like. Moreover, the shape of themarker may be selected from a wide variety of shapes that may suggestthemselves. It is intended that the particular illustrative embodimentshall not be limiting on the claims beyond the clear meaning of thelanguage therein employed.

I claim:

1. In a liquid marker having a replaceable ink cartridge in combination,an outer barrel open at one end thereof and having an internallythreaded insert in the opposite end thereof, an ink cartridge withinsaid barrel, said cartridge having a major and a minor external diameterforming an external annular shoulder at the junction of said diameters,an absorbent ink reservoir within said cartridge, a writing nib incontact with said absorbent ink reservoir and extending from one end ofsaid cartridge, an end plug having a diameter that is less than saidminor diameter of said cartridge closing the opposite end of saidcartridge, external screw threads formed in said end plug, said threadsof said plug being adapted to engage said threads of said insert anddraw the open end of said outer barrel into tight engagement with saidannular shoulder.

References Cited UNITED STATES PATENTS 1,449,234 3/1923 Laffin 401-1332,061,059 11/1936 Carlson 40l-134 2,381,898 -8/1945 Gergely 4011343,048,879 8/1962 Rosenthal 401-199 3,355,239 11/1967 Albrecht 401-198FOREIGN PATENTS 1,008,626 2/1952 France.

LAWRENCE CHARLES, Primary Examiner

